“Rock Hard” and similar so-called “natural” supplements for men often contain potentially dangerous drugs — some of which have never been tested on animals, let alone humans.

In an editorial published in JAMA Internal Medicine, Pieter Cohen, assistant professor of medicine at Harvard Medical School and a colleague collected some of the lesser known facts about an industry that produces millions of pills.

The industry likely generates tens of millions, if not billions of dollars in profits— but is almost entirely free of government oversight.

Dangers of Male S.exual Supplements

Here’s what they found:

* A product sold as “Rock Hard for Men” in 2012 turned out to contain not only counterfeit Cialis (tadalafil)— but also a diabetes drug that can be deadly if used incorrectly. A similar combination killed more than a dozen men in Asia in 2009.

* One Utah company alone produced more than a million pharmaceutically-tainted pills monthly, earning $2 million between 2007 and 2010, according to an indictment issued in one of the few cases brought against such manufacturers.

* More than three-quarters of male enhancement supplements tested in one study in Singapore contained pharmaceuticals that were not disclosed— and half of them were present in higher doses than recommended.

* Over 45 different versions of drugs in the same class of Viagra have now been found in male sexual supplements.

A Dutch study found that 75% of the products sold in the Netherlands contained at least one analogue, or chemical variant that has the same effect as Viagra.

* A product called “Mojo Nights” recently analyzed by the Food and Drug Administration (FDA) included not just counterfeit Viagra, but also three different analogue drugs.

* Just last week, the FDA identified three tainted supplements: “Vicerex” and “Bullet Proof,” which contain counterfeit Cialis and “Lightning ROD,” which includes an analogue of Viagra. - Online Sources